September 30

What Are The Different Types Of Lisps And When Do They Start To Develop?

One of the most common and noticeable orofacial myofunctional disorders is a lisp. A lisp is a term used when a child has difficulty pronouncing certain letters, such as ‘s’ or ‘z’. Although we refer to most mispronunciations as ‘lisps,’ there are actually several different types of lisps that a child can develop. Here we explain the different types of lisps and when they start to develop.

When Do Lisps Develop?

As your child develops their speech skills, you might notice they have a slight lisp. Because it can be difficult to pronounce an ‘s’ or ‘z’ in early speech anyway, a temporary lisp is not uncommon. As a child learns to pronounce these letters correctly, the lisp will likely fade. 

However, if the lisp continues beyond the age of four, or if there are recognizable speech delays, it’s possible that the tongue’s resting position may be abnormal (sometimes due to thumb-sucking or extended pacifier/bottle use). If that’s the case, and the tongue’s muscles aren’t working as they should, your child may develop a more prominent lisp that can be corrected with myofunctional therapy exercises

The Four Types of Lisps

There are four different types of lisps and are as follows: 

Interdental Lisp

An interdental lisp is probably the most common type of lisp. The interdental lisp is when a child has difficulty pronouncing an ‘s’ or ‘z’ sound. Rather, it sounds like “th” instead. The incorrect tongue placement where the tongue protrudes between the front teeth causes this mispronunciation.

Dentalized Lisp

This is very close to an interdental lisp, but in this case the tongue pushes against the back of the front teeth. This affects airflow, forcing it forward, which can cause a muffled sound when your child speaks.

Lateral Lisp

This is often referred to as the slushy lisp and for good reason. If your child’s speech sounds very wet it is because their tongue is in a position that allows air to escape at the sides.

Palatal Lisp

This is a less common type of lisp, but results in difficulty pronouncing ‘s’ and ‘z’ because the tongue touches the palate of the mouth.

How To Identify a Lisp

In most cases a lisp will be obvious due to pronunciation issues, or a “slushy” sound. As mentioned, it is common for toddlers learning to speak to experience various pronunciation issues. By your child’s school years however, if your child continues to lisp, or the lisp has become more exaggerated, you should speak to a myofunctional therapist to see if the issue may be due to a tongue thrust or poor tongue posture. 

A myofunctional therapist can help determine the cause of the lisp. If it’s related to the incorrect placement of the tongue, or weak tongue muscles, a series of myofunctional exercises can help retrain your child to use proper tongue placement to clarify their speech. 

If you think your child may have a lisp, schedule an appointment with the Bloom Center for Sleep & Airway Health. We’ll get to know your child and evaluate their unique needs.

To learn more about myofunctional therapy and lisps, visit this page here


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